The purpose of this project is to study radiation sensitizing compounds and their ability to increase the effect of radiation in sterilizing neoplastic cells. The plan is to take patients who have carcinoma of the esophagus that appears to be clinically confined to the mediastinum and give all patients irradiation. Half the patients will receive misonidazole, a hypoxic cell sensitizer, administered by an intravenous method. Following completion of the radiotherapy, survival, freedom from lapse, and tumor will all be evaluated. In addition, these patients, who are frequently cachectic, will serve as the basis for controlled studies of total parenteral nutrition. In addition, this study utilizes an innovative fractionation schedule for the irradiation (400 rad twice weekly, rather than 200 rads daily, 2 days per week).